The Bland–Altman analysis for repeated measures on 10-minute time windows in the awake state (around 7 PM) and during sleep (around 12 AM) was used to compare OHR and HRECG [6]. The Mann–Whitney U-test was used to compare the average HRECG and

Firstly, this study does research on the quantitative uation of the acoustic performance of the planar ultrasonic array sensors. Sparse signal decomposition theory is then applied to find three different directions of arrival (DOAs) of the signal